Caster



Patented l, 1932 testina .errar ice JOHN T. GRAHAM, OF CREIGHTON,PENNSYLVANIA, ASSIGNOR OF ONE-RALF T0 il' F. KOWK, GF CREIGHTON,PENNSYLVANIA v CASTER Application led February 19, 1932. Serial No.593,992.l

My invention relates to casters, and while primarily intended for use assupports'for furniture and the like, it will be obvious that the devicemay be employed for an)7 purposes wherein it is found to be applicable.

important objects of this invention are to provide a device of thecharacter described, in a manner hereinafter referred to, which embodiesa supporting ball mounted in ball bearings allowing universal rotarymovenient of the former, which is simple in its construction andarrangement, smooth running and noiseless, strong, durable and eiiicientin its use, and comparatively inexpensive to manufacture.

`With the foregoing and other objects in view which will appear vas thedescription proceeds, the invention resides in the novel construction,combination and arrangement of parts hereinafter described andillustrated in the accompanying drawing, wherein like numerals ofreference designate correspond ing parts throughout the several viewsand wherein:

Figure l is a side'e'levational view, partly in cross section, of acaster constructed in accordance with my invention, and illustrating itsapplication and connection as a support.

Figure 2 is a bottom plan view thereof.

Figure 3 is a side elevational view of my improved device.

Figure 4 is a side elevational view of the duplex race for the ballbearings.

Referring in detail to the drawing l denotes a rounded leg member ofsome piece of furniture provided at its lower end with a verticallydisposed socket 2 having a flared lower end. A. tubular lin-er 3, havinga similarly flared lower end is fixed in the socket 2 to prevent wear tothe latter from the operation of the caster element.

rihe caster comprises a body portion 4 consisting of a verticallydisposed stem 5 adapted for insertion in the tubular liner 3 forconnecting the body portion 4 to the leg` member l. The lower end of thestem 5 is integrally formed with, welded or otherwise secured to acylindrical, hollow casing 6 having an open low-er end, and acurvilinear top 7, thevouter marginal edge, of which is flat, asindicated at 8. i

A duplex race member 9, for housing bearingA balls 10, isfixedly mountedin the casing 6 by being forced therein under pressureor in any other Ksuitable manner. The race member 9 has its lower end formed to provide acircumferentially vextending groove l1, and its upper end to provide thecircumferentially extending seat l2, which latter is substantiallyL,shaped in transverse cross section. The groove 1l and seat l2 areprovided by the formation of the intermediate vreduced connectingportion 13.

When the race member 9 is fixed in position in the casing 6, as clearlyshown in Figure; l of the drawing, the fiat top portion 8, of the casing6, forms a complemental top wall for-the seat 1.2,l providing, incombination with the latter, a complete groove disposed parallel to andspaced from the groove 1l.

The groove 11 and the seatr12 are each filled with a circumferentiallyalignedrow of bearing balls lO before the race member 9 issecured inposition in the casing 6. p A comparatively large supporting ball 14 is`mounted in the race member 9, and' is engaged only by the two rows ofbearing balls l0, mounted respectively in the groove 1l and in the seatl2. The row of bearing balls 10 mounted in the seat 12 are disposedabove the diametric center of the supporting ball l14, and the row ofbearing balls 10 mounted in the groove ll are disposed below thevdiametric center of the supporting ball 14.

By this arrangement the latter will be maintained in position in therace member 9 and at the same time allow a free universal rotarymovement of the supporting ball lll.

ln assembling my improved device, the bearing balls l0 are first placedin the groove 1l of the race member 9, the supporting ball 14 then beingpositioned in the race member y9 through the open top thereof. Bearingballs 10 are now placed in the seat 12 after which the race member 9 isforced in position in the casing 6 in any suitable manner.

While illustrating and describing a stem and socket connection forattaching my improved device for use, it will be obvious that any othersuitable attaching elements therefor may be employed to best meetconditions found in practice.

The present invention provides a most effi: cient device of its kind,Which may be conveniently employed for replacing casters of the usualconstruction novv in common use,- and which Will greatly facilitate themove-v mentpof heavy objects equippedtherewith.' 110. Y Vhat I claim is:,p

l. A caster for the purpose set forth confprising a body portionincluding a hollow cylindrical casing, said casing having a curvilineartop providedy WithI a flat-'outer marf5. ginal edge, a duplex racemember mounted inV saidcasing andformedvvith acircumferentially'extending ygroove at its lower end andA withacircumferentiallyextending seat altits-upperend, saidseat beingsubstantially 2;@ L-shapedv in` transverse cross section and forming agroove when combined With said flatinarginal-edgeof saideasingtopbearing ballsl carried in said seat and in said groove, asupportinglballpositioned in said 215 race member andbein'g engaged by said bearingballs, said body portion including an attaching,element.y v

2. A- caster. for the purpose set-forthcomprising a. body portionprovided with an at- 3o tachingj element andincludi-ng ahollowcylindriealycasing, saidcasing-having a curvilinear topprovided With aflaty outer' marginal edge, a duplex race member-.fixed'in Saidcasingand formed withV a circumferen-A 35 ti-ally extending groove on itslowerend and With a circum-ferentially extending seat on its upperend,saidV seat being substantiallyv |..f-shap'ed.r in transversecrosssection and forming a groove whenl combinedzwith said 40 fiat marginaledge offsaid casing-top, bearingballs vcarried insaid seatand-j in saidgroove, a supporting ball positioned =`in said racemember, the bearingballs carriedin said seat Iengaging the said supporting bal-l above 45its diametrie center and the bearing bal-ls l carried-Ain said grooveengaging the said-sup4 porting ball below itsv diametric center.

In testimony whereof Y I- affix my signature.

50 JOHN T. GRAHAM.;

